Comtech EF Data CDM-600/600L - Manual (Page 90)

CDM-600/600L Open Network Satellite Modem Revision 3
Front Panel Operation MN/CDM600L.IOM
5–14
When Drop Framing or the G.703 interface type is used, the [ ↑][↓] arrow keys will scroll through
the available data rates. If in Drop Mode and the data rate is edited to 1920 kbps, a comment is
shown to indicate that E1 fixed channel mode will be implemented.
When G.703 is used and the Modem is Hardware Revision 2.0 or higher, three auxiliary rates will
also be available (512, 1024 and 2048 kbps) indicated by the word AUX appearing to the right of
the decimal place (e.g.,
00512.AUX kbps
).
Refer to Sect. 3.3.4.2 J10A IDI, J11A DDO Connectors for additional information about how to
connect the cables for the AUX data rates.
The bottom line permits the user to select the data inversion feature (added for compatibility with
certain older equipment). Set DATA INVERT to ON or OFF using the [
↑][↓] arrow keys, then
press [ENT] when done.
5.4.3.6 CONFIG: TX
Æ SCRAMBLER
TX SCRAMBLER = NORMAL (NORMAL,OFF)
ENCODER SCRAMBLER
Select Normal or Off using the [ ↑][↓] arrow keys, then press [ENT]
The choice of scrambler used for Normal is selected automatically, and depends on the exact
operating mode. For example:
• If no framing is being used, the ITU V.35 scrambler (Intelsat variant) will be used.
• If IBS framing is selected, the IESS-309 scrambler will be used, etc.
If LDPC encoding is selected, the standard ITU V.35 scrambler will be used.
If Turbo encoding is selected, a second scrambler, IESS-315 V.35, is available instead of the TPC
scrambler:
TX SCRAMBLER = IESS (NORMAL, IESS, OFF)
IESS-315 V.35 SCRAMBLER
5.4.4 CONFIG: RX
RX-IF DECODER DEMOD DATA DESCRAM EbNo
DATA=00064.000kbps SYMBOL=00064.000ksym
From the top line, using the [ ←][→] arrow keys, select the parameter – RxIF, Decoder, Demod,
Data, Descram, or EbNo – then press [ENT]. On the bottom line, read-only Data/Symbol rate
information is provided.